PhotoShop is limited to the length of file it can print (between 1.5m-2.25m, depending on pixels/DPI) - so save the file as a PDF and print from Acrobat to produce 4m+ continuous prints on the Epson 9800 using the native Epson OS-X driver.
Apparently, Epson say that Apple OS-X is limited to 90.5" prints - but I've printed far longer than this using the above system of PDF printing (although strangely, the 9600 can't print the same 4m PDF file the 9800 can). The only problem with PDF printing is the limit on PDF files themselves - which are allegedly limited to 30,000 pixels or the Operating Systems file size limit (4Gb+ on OSX).
Although the autonomous car is not quite ready, a lights out print operation is something you can do right now if you have a comprehensive Print MIS (Management Information System). The advantages can put money on your bottom line. So what’s your next step? Link to Article